Here you go

Swipe UI for jailbroken IOS

or...

N9 Ui on jailbroken IOS

oh, and you need a keyboard too http://www.thinkgeek.com/gadgets/cellphone/ea6d/

Any combination of the above will give you an iphone that will impress even the most ardent of nokia fanboy

If you dig far enough through the cydia devel pages you will find some great projects to get your teeth into. I have a few workmates who are heavy in to the Jailbreak scene and you know what? We have greater discussions about the mobile phone scene together than we do with any of the android users in our team.



Edit: check this theme out bit more n9-ish